U.S. Rep. Mike Coffman and Morgan Carroll, photographed at Univision TV studios on October 4, 2016.

On paper, Mike Coffman’s suburban Denver congressional district — which now has slightly more Democrats than Republicans and plenty of Latino voters — should make him sweat.

It hasn’t worked out that way.

In the last two elections, the Aurora Republican has blown two well-financed rising Democratic stars out of the water. His latest casualty was state Sen. Morgan Carroll, who lost to Coffman by 8.6 percentage points in unofficial results Tuesday after the two waged the costliest congressional campaign in the state.

RJ Sangosti, The Denver Post

U.S. Rep. Mike Coffman, and his wife, Colorado Attorney General Cynthia Coffman, takes the stage during the Colorado Republicans Election Night party at the DoubleTree Hilton in the Denver Tech Center, Nov. 8.

“He’s officially bulletproof,” said Eric Sondermann, a Denver-based political analyst. “There’s one and only one threat that I can see to Mike Coffman’s tenure in Congress, and that’s redistricting. And that doesn’t happen until just prior to the 2022 election.”

Coffman again thwarted national Democrats who had hoped this presidential election would offer their best shot at unseating him. Two years ago, in a midterm election that favored Republicans, Coffman beat former Colorado House Speaker Andrew Romanoff by only slightly more — 8.9 percentage points.

Five years ago, Carroll served on the state’s redistricting committee in a process that resulted in Colorado Democrats redrawing the 6th Congressional District to make it competitive. Coffman, since surviving a close call in the 2012 election, has adjusted some of his more conservative positions on immigration and other issues to better fit the district. He’s also taken Spanish lessons.

And he will now serve a fifth term, giving Democrats a pause to mull whether it’s worth it to invest millions of dollars in yet another challenge in 2018.

Sondermann is among observers who see Coffman cementing his status as a hard-to-beat incumbent, despite the otherwise competitive makeup of the district. A colleague who has earned the same distinction is Democratic Congressman Ed Perlmutter of Golden.

“He can have that seat as long as he wants it,” Sondermann predicted. “I have a hard time seeing Democrats continuing to invest serious resources in this race.”

Nothing is certain in politics, of course. In two years’ time, what looks like a safe seat now might be transformed into a cutthroat race again if Democrats sense voter unease with President-elect Donald Trump and the Republican-controlled Congress.

And Coffman, who separated himself from Trump during the campaign — he said he’d stand up to Trump in a TV ad — now faces pressure to follow through on that pledge after Trump’s surprise win.

“Now more than ever, with Donald Trump as president … we’re going to hold him accountable to what he said,” said Lizeth Chacon, executive director of Colorado People’s Action. The group opposed Coffman’s re-election this year in part because he didn’t support a 2013 comprehensive immigration reform bill.

But Coffman can take comfort in his performance Tuesday. He drew support from some voters who also cast ballots for Democratic presidential candidate Hillary Clinton, who won Colorado. In Arapahoe County, whose voters live mostly in the 6th District, Clinton won the votes of nearly 53 percent, while Coffman pulled 48.5 percent support — nearly 10 percentage points ahead of Trump.

A spokesman for the Democratic Congressional Campaign Committee didn’t return requests for comment about its outlook for 2018. The DCCC sunk at least $3.2 million into defeating Coffman this year, according to the Center for Responsive Politics.

“Of course we continue to believe that Mike Coffman doesn’t adequately represent the district,” said Chris Meagher, spokesman for the Colorado Democratic Party. “And while it’s too soon to talk about how we approach 2018, I will say that this election has already awoken people who want to get involved and volunteer to make sure this year is not repeated.”

Said Laura Chapin, a Democratic political consultant: “In an off-year (election), nobody should ever go unopposed. But we all know that the hardest thing in politics is to take out an incumbent, regardless of party.

“That is an uphill battle, and Democrats are aware of that reality.”

Republicans loyal to Coffman long have warned against underestimating his ability to forge connections with immigrant communities and other groups.

“He isn’t perfect,” said Josh Penry, a consultant to Coffman’s campaign, who then referred to Coffman’s much-publicized 2012 comment that indulged in birtherism. “He made a stupid remark about President Obama six years ago and apologized the next day. He’s evolved on immigration. But from that, the Democrats try to turn him into some kind of craven Attila the Hun? It just doesn’t work, because it doesn’t fit the Mike Coffman people see and know.”

After he cruised to re-election last week, political observers similarly were quick to deflate any remaining Democratic illusions.

“This year was probably as difficult as re-elections are likely to get for Coffman,” said Seth Masket, a political science professor at the University of Denver. “Unless 2018 sees a very strong anti-Trump tide across the nation, Coffman is probably safe in this district.”

Jon Murray is The Denver Post's city hall reporter. His coverage focuses on Denver Mayor Michael Hancock, the workings of the City Council and city's government interactions with Denver's people, from neighborhood issues to regulation of the marijuana industry. A Colorado native, he joined The Denver Post in 2014 after reporting on city government and the legal system for The Indianapolis Star.

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